I'm planning on only hosting Wordpress so I need to make some changes to the php5-fpm templates that get applied to each vhost and am not sure where these templates are located and if I can simply edit them and if they will get replaced with the next ISPCFG update or if there is another way of permanently committing my changes?

Is there a place where I can find documentation on where these "internal" templates and such are located?

Thanks. I had meanwhile found another thread mentioning this but am not sure how this works: I don't want to add additional code but lets say remove or change the templates so if I copy over one of the templates into the conf-custom folder will they take precedence and "over-rule" an original template inside the /usr/local/ispconfig/server/conf/ folder?